Consumers have increasingly placed a premium on compact yet durable, space saving devices which move cargo, a fact that is easily demonstrated by the exponential growth in wheeled luggage devices using recessing, telescoping handles, as well as the ever expanding number of utility carts and four wheel wagons providing folding or recessing handles. It is often the stated object of many of these latter mentioned cart or wagon devices to provide for a simple design which includes a folding or recessing handle structure, thereby allowing for easier transport of devices, e.g., in a car trunk, or to allow for compact display or storage. However, in actuality, there is little that is compact or space-saving in most of these devices which characteristically incorporate a fixed or one piece cargo area or "well," and set of two or four wheels which are affixed to an axle, and which provide no method for any of the wheels to fold or recess in a space saving manner. In general, merely recessing or folding a handle structure alone goes a very little way in creating a truly space-saving cart or wagon device.
Over many years, countless designs have been proposed for folding or collapsing rolling carts and wagons. Most suffer from a number of problems, including those relating to difficulty of manufacture, the need for many detachable parts, or difficulty in use, i.e., the requirement for non-intuitive actions by a consumer in order to determine how to collapse or set-up the cart or wagon. For example, see U.S. Pat. No. 4,109,926 (Lane), U.S. Pat. No. 4,856,810 (Smith), U.S. Pat. No. 4,765,643 (Pappanikolaou). Previous patents have also generally disclosed folding side, front and rear walls which fold or collapse in various fashions (see, e.g., U.S. Pat. No. 4,887,836 (Simjian)).
Further, numerous patents have described methods to fold or nest cart or wagon handles using various methods, including articulating joints, detachable handles, or pivoting handle structures. For example, see U.S. Pat. No. 2,350,062 (Mosier), U.S. Pat. No. 2,984,499 (Humphrey), U.S. Pat. No. 4,889,360 (Havlovitz) and U.S. Pat. No. 5,692,761 (Havlovitz). The devices of the Havlovitz patents are notable for the simplicity of their design and both include a folding handle. The primary deficiency of the devices of the Havlovitz Patents, despite their simplicity, is that the devices are not truly compact designs. Moreover, in the latter patent, it is quite awkward for the consumer to fold the handle down, since this requires lifting of the entire cart off the ground to achieve the recess handle position. The prior art also discloses wheel support arms which pivot through, in general, 90.degree. along an axis adjacent to the base or underside of the wheeled device, but, in general, such wheels support arms must be folded out from the underside of the device and generally require some other interfitting device or part to cooperate with the wheel support arms to "lock" or resiliently retain the pivoting wheel structure in place.
In general, the invention overcomes a large number of deficiencies and disadvantages in the prior art carts and wagons. It is believed that these deficiencies and disadvantages have prevented the manufacture of a truly compact, space saving wheeled device having a very thin profile. The invention also provides a folding cart or wagon which is simple to assemble and manufacture, which sets up in seconds, which includes a minimum number of separate parts, which has no part which normally detaches, which is very simple to operate properly, and which does not require a consumer to occupy an awkward position to set up.
Objects of the invention include the following: to provide a unique 270.degree. pivoting wheel and wheel support structure which may be used with several different types of support arm structures, including the provision of retention means between the support arm structure and the base and/or walls of the various two or four-wheel devices described hereinbelow; to provide a unique ultra-flat, compact and space saving construction which involves recessing of a generally "U" shaped handle (or two straight handles) into the profile of such a device, as well as in the provision of cooperating sleeves constructed as a part of the folding side walls, to provide that the handle, whether generally "U" shaped or in the form of two straight handles, telescopes and engages the outer portion of the cart base along a slide path, is provided with detents so that the handle may recess directly inside a sleeve or cylinder around which a pivoting wheel support structure pivots; to provide several alternative embodiments for a simple kickstand or other underside support for the device; to provide for cooperation and interlocking between the walls of the cart in the movement thereof between their folded raised position, to further provide a four-wheel wagon or cart embodiment which includes a center pull handle which folds and nests flat into the base or bed of the wagon, and provide for a zippered carry bag made of a mesh, or other suitable material, which is capable of being rolled up and stored in a storage cavity provided in either end of the base of the cart, as well as a shoulder strap for transporting the collapsed cart, and to provide for a fold-down drink and/or implement holder as a part of a wall of the wagon or cart, to provide for a number of alternative wheel structures and support arm structures, and to provide a number of base underside strengthening and support embodiments, as well as other important improvements as further described hereinafter.
According to one aspect of the invention, a wheeled carrier device is provided which comprises a base member; a plurality of foldable walls supported on the base member and movable between an erected state wherein the walls define a carrier space and a collapsed state wherein the walls are folded on top of the base member; at least two wheels; and wheel mounting means for pivotably mounting the at least two wheels on the device on opposite sides thereof such that the at least two wheels are movable through 270.degree. from a first, operative position wherein the wheels support the carrier device and a second, inoperative position wherein the wheels are folded over on top of the folded walls in the collapsed state of the latter.
Preferably, the wheeled carrier device further comprises a handle affixed to the carrier device and movable between an operative state wherein the handle can be used to pull the carrier device and an inoperative state wherein the handle is stowed in substantially flush relation with the remainder of the carrier in the collapsed state of the walls.
In one preferred embodiment of the handle, the handle comprises a substantially U-shaped handle member including parallel arms pivotably connected to the carrier device. The foldable walls include side walls and these side walls preferably each include handle receiving means for supporting the parallel arms in the operative state of the handle. The parallel arms of said U-shaped handle member advantageously comprise telescoping arm elements which telescope between an extended position in the operative state of the handle and a retracted position in the inoperative state of the handle. The handle member further comprises releasable means for retaining the telescoping arm elements in the retracted state thereof.
In a further preferred embodiment thereof, the handle preferably comprises an elongate handle member pivotably connected to one end of the carrier device and movable to a folded down storage position wherein the handle extends longitudinally of the carrier device in the collapsed state of the walls.
In an advantageous embodiment, the walls comprise first and second spaced, parallel walls and third and fourth spaced, parallel walls extending orthogonally to the first and second walls, the first and second walls each having and inwardly facing surface including at least one curved channel therein at each end thereof extending between side and bottom edges thereof, and the third and fourth walls including projecting elements received in the channels for enabling a downward folding movement of the third and fourth walls to collapsed positions wherein the third and fourth walls fold down on the base member.
The wheel mounting means preferably includes a wheel support member including oppositely extending mounting elements and the base member of the carrier device preferably includes spaced, opposed cavities therein in which the mounting elements are pivotably received. The wheel mounting means preferably includes manually operable releasable means for, when engaged, serving to retain the at least two wheels in the operative position thereof.
In an embodiment wherein the carrier device has two wheels the carrier device further comprises an erectable support element affixed to the carrier device in spaced relation to the two wheels for, when erected, supporting the base member of the carrier device in a substantially horizontal position. In a preferred implementation, the erectable support element comprises a U-shaped support member including support arms pivotably connected to the base member and pivotably to a nested position with respect to the base member.
Advantageously, the wheeled carrier device further comprises an erectable tray element for, when erected, providing a support surface.
The wheeled carrier device preferably further comprises means defining an elongate storage space at one end of the device, and a rollable carrier bag stowable in said storage space.
In an embodiment wherein the cart has four wheels, two of the wheels, in the operative state thereof, are rotatable through 360.degree. beneath the base member.
According to a further aspect of the invention, a wheeled carrier device is provided which comprises a base member; a plurality of foldable end walls and side walls supported on said base member and movable between an erected state wherein said walls define a carrier space and a collapsed state wherein the walls are folded on top of said base member; at least two wheels; and a handle affixed to the carrier device and movable between an operative state wherein the handle can be used to pull the carrier device and an inoperative state wherein the handle is stowed in substantially flush relation with the remainder of the carrier in the collapsed state of said walls, the handle including handle arms disposed on opposite sides of the side walls, and the side walls each including handle arm receiving means for supporting the handle arms in the operative state of said handle.
As set forth above, the handle advantageously comprises a substantially U-shaped handle member and the handle arms comprise parallel arms of the U-shaped handle member pivotably connected to the carrier device. As in the first aspect of the invention, the walls preferably comprise first and second spaced, parallel walls and third and fourth spaced, parallel walls extending orthogonally to the first and second walls, said first and second walls each having an inwardly facing surface including at least one curved channel therein at each end thereof extending between side and bottom edges thereof, and the third and fourth walls including projecting elements received in the channels for enabling a downward folding movement of the third and fourth walls to collapsed positions wherein said third and fourth walls fold down on the base member.
Similar to the first aspect of the invention, each wheel mounting means includes a wheel support member including oppositely extending mounting elements and the base member of the carrier device includes spaced, opposed cavities therein in which the mounting elements are pivotably received.
In accordance with a third aspect of the invention, a wheeled carrier device is provided which comprises: a base member; a plurality of foldable end walls and side walls supported on said base member and movable between an erected state wherein said walls define a carrier space and a collapsed state wherein the walls are folded on top of said base member; at least two wheels; and a handle affixed to the carrier device and movable between an operative state wherein the handle can be used to pull the carrier device and an inoperative state wherein the handle is stowed in substantially flush relation with the remainder of the carrier in the collapsed state of said walls, the handle comprising an elongate handle member pivotably connected to the carrier device at one end thereof centrally of said one end and being pivoted back, in said operative state, to a folded down position between the folded side walls in the collapsed state of the side walls.
Further features and advantages of the present invention will be set forth in, or apparent from, the detailed description of preferred embodiments thereof which follows.